SERPINE1 and irritable bowel syndrome: PAI-1 emerged recently as a critical link between the epithelium and inflammation, which showed elevated mucosal gene expression in patients with IBD who did not respond to anti-TNF biologic therapy.11 The present study demonstrated that the serum, mucosal, and faecal PAI-1 concentration is selectively elevated in IBD patients showing clinical and endoscopic activity but not in other organic gastrointestinal diseases, and decreased significantly upon successful therapy in responders.